Using QMutex in recursive mode is deprecated.

xapian/xapiansearchstore.cpp

@@ -19,7 +19,7 @@ using namespace Akonadi::Search;
 
 XapianSearchStore::XapianSearchStore(QObject *parent)
     : SearchStore(parent)
-    , m_mutex(QMutex::Recursive)
+    , m_mutex()
     , m_nextId(1)
 {
 }

xapian/xapiansearchstore.h

@@ -89,7 +89,7 @@ protected:
     Xapian::Database *xapianDb();
 
 protected:
-    QMutex m_mutex;
+    QRecursiveMutex m_mutex;
 
 private:
     Xapian::Query toXapianQuery(const Term &term);